The family of a young man with mental disabilities wants DPS troopers to undergo sensitivity training after their 22-year-old son was tackled by a trooper inside a fast food restaurant Wednesday.

Bill and Lisa Polkinghorn said their son, David, is traumatized after a DPS trooper tackled him inside a Chick-Fil-A restaurant, suspecting him of stealing credit cards.

"He told me, 'I thought she was going to kill me,'" Lisa said.

Lisa said her son's wallet broke as they pulled into the Chick-Fil-A parking lot Wednesday around 6 p.m.

"He has gift cards that he was given for his birthday recently and he keeps them in a little plastic wallet, like a child's wallet that he bought at the dollar store," Lisa said.

She waited in the car as he took out the gift cards and threw the wallet in the trash can of a nearby restaurant. That's what caught the attention of the DPS trooper. The trooper followed David down the sidewalk inside the Chick-Fil-A.

According to a DPS spokesman, the trooper started asking David where he got the cards. Lisa said her son did not understand what was happening.

Security video shows David walking away and the trooper forcing him to the ground and later placing him in handcuffs.

David is not facing any charges for resisting arrest.

However, the Polkinghorns said their son is still suffering.

"He went home that night and didn't talk to us," Lisa said. "He kept the blanket over his head. He was still terrified."

The family's goal is to increase troopers' sensitivity toward people with special needs.

"The police officer should have noticed the way he walks, his mannerisms, the way he talks, all are signs that he has a mental disability," David's father, Bill Polkinghorn said.

DPS did not find reason to investigate the trooper's behavior. A spokesman said the trooper sustained minor injuries as a result of the incident but is not pressing charges.

Here is the full statement from the DPS:

According to preliminary information, a Texas Department of Public Safety (DPS) Trooper observed an unidentified male enter a Conroe area restaurant on May 3 at approximately 6 p.m. According to the Trooper, the man was observed discarding a wallet into a trash can and leaving immediately afterwards; he then entered another nearby restaurant.

The Trooper detained the man, later identified as David Polkinghorn, in the restaurant to determine if the suspicious activity was related to criminal activity. The Trooper reported Polkinghorn walked away from her, and began to resist but was eventually restrained. During the incident, the Trooper sustained minor injuries. Polkinghorn was evaluated by paramedics, but had no visible injuries.

Following the arrest, the Trooper learned of Polkinghorn's reported condition. After consulting with prosecutors, the Trooper declined to file charges for interference with public duties or assault on a peace officer, and released Polkinghorn to the care of his mother.

At this time, no complaint has been filed with the Office of Inspector General related to this incident.